Slide-valve.



No. 892,278. PATENTED JUNE 30, 1908.

M. J. MALONEY.

SLIDE VALVE.

APPLIOATION rmm JULY 10.1901.

2 SHEETS-SHEET 1.

H! "on": PETERS cc.. wuumomm'u. c.

PATENTED JUNE 8Q, 1908.

M. J. MALONBY.

SLIDE VALVE.

APPLICATION FILED JULY 10.1907.

2 SHEETS-SHEET 2.

UNITED STATES PATENT OFFICE.

MATTHEW J. MALONEY, OF MISSOULA, MONTANA.

SLIDE -VALVE To all whom it may concern:

Be it known that I, MATTHEW J. MALONEY, a subject of the King of Great Britain, (who has declared his intention of becoming a citizen of the United States,) residin at Missoula, in the county of Missoula anc State of Montana, have invented new and useful Inirovements in Slide-Valve Mechanism for ngines, of which the following is a specification.

This invention relates to slide valve mechanism for engines.

In that form of embodiment of the invention which I have selected for illustration in the accompanying drawin s forming a part of this specification, the vsilve is represented in connection with a steam engine. It may, however, be used with advantage in other connections, as it is not essential that steam be the fiuid which is utilized as the ropelling medium for the piston or equiva ent part. The parts of the mechanism are so disposed that, when exhaust is to take place, this can occur without back pressure on the piston. This result I obtain in the present instance by partially covering a port through which steam is admitted to the cylinder and wholly uncovering another port from which steam is exhausted from said cylinder. This difference in area of said ports is obtained by the valve.

Referring to said drawings: Figure l is a top plan view of the cylinder of a steam engine equipped with valve mechanism involving my invention, the cover of the steamchest and valve being removed. Fig. 2 is a similar view with the valve in place. Figs. 3 and 4 are longitudinal and transverse sectional views respectively of the cylinder with all the parts in operative positions. Fig. 5 is a perspective view on an enlarged scale of the valve. Fig. 6 is a detail view in section of a modified form of valve.

Like characters refer to like arts through- Specification of Letters Patent.

Application filed July 10, 1907.

Patented June 30, 1908.

Serial No. 383,060.

said cylinder 2 for the purpose of controlling the ports 6 and 7. The valve, although carried by the cylinder, is not directly mounted thereon but travels upon a wearplate as 2 substantially co-extensive with the steamchest and resting on the cylinder. The ports 6 and 7 are formed respectively in the cylinder 2 and wear-plate 2. The ports 6 and 7 constitute alternately supply and exhaust ports for example, when port 6 is open to admit live steam to the cylinder 2, the opposite port 7 is open to atmosphere. It is not essential what the shape of these two ports be, although they are re resented as being approximately rectangu ar, and they, of course, communicate with the interior of the cylinder 2.

The valve '5 includes in its make-up two substantially similar heads 8 and 9 which may be connected in any suitable wa for example, by the com anion bars 10. If desired, the heads 8 an 9 and bars 10 may be made integral by casting, and the cross-bars 11 may, if desired, be integral with the other parts of said Valve. The latter has a re ciprocatory motion in the steam-chest, the head 8 thereof controlling the port 6, and the head 9 controlling the port 7. The said heads are of such character, as will be hereinafter set forth, as to partially throttle and wholly uncover the ports 6 and 7 in alternation. I The two valve heads 8 and 9 are fitted with packing strips each designated by 12, which are set in grooves extending across top and on both ends of said heads to obtain a steam-tight fit. The valve 5 is shown as having a flat top and a concaved bottom, the latter conforming practically to the curvature of the upper portion of the cylinder, while the fiat top is situated immediately below the flat under surface of the cover of the steam-chest 4. This valve can be used on flat seat also.

In Fig. 6 I have shown a modified form of valve, the same being designated by 5. Said valve 5 has circular or concave top same as seat, but the workin principle is just the same as that of the Va ve 5.

WVhere the boiler, not shown, and cylinder 2 are together as on a locomotive, steam will be admitted initially through ports in steam saddle to center of steam-chest by way of the port or inlet 13 and will be exhausted at ends of steam-cl1est through ports 14: and 15 into ports in steam saddle, not shown.

When the boiler and cylinder are not together, pipe connections will be used, but the admission of steam to and the exhaust of the same from the steam-chest will be the same.

The wear-plate 2 is provided with wear portions as 16 and 17 shaped transversely'to conform to thecurvature of the under portions or seats of the balancing bars 11 to provide for the proper balancing of the valve 5 when the heads 8 and 9 thereof are passing over the ports 6 and 7. Said bars 11 have steam-chest pressure under and over them at all times, except when the heads 8 and 9 are crossing the ports 6 and 7,- at which time the said bars 11 are resting or seating on the raised portions 16 and 17, which does not permit steam pressure to get under-said bars, the steam-chest pressure being on top of the bars and holding the valve down, and the cylinder pressure acting against the under sides of the two valve heads 8 and 9. Cylinder pressure under the valve heads and steam-chest pressure on top of the bars are counter-acting each other. When valve heads 8 and 9 pass off the ports 6 and 7 the balancing bars 11 are passing off their seats on the raised portions 16 and 17, thereby permitting steam-chest pressure to act against the under sides of said bars. Therefore, when there is no upward pressure on the valve heads, there is no downward pressure on said bars, by virtue of which the valve is perfectly balanced when the heads thereof are crossing the two ports 6 and 7.

It will be seen that the inner faces of the two valve heads 8 and 9 are upon a slant. In the present case these two slanting inner faces converge outwardly or toward the cover of thesteam-chest, and an advantage follows this relation of said faces. The valve, as is obvious, is subjected to steam pressure downwardly and I so dispose these two faces that they are adapted to receive upward pressure from the steam, by virtue of which the said heads are balanced; in other words, the opposite pressures acting against the heads are substantially equalized.

The head 8'is shown as having on 1ts inner side a recess, an aperture, or cut-away portion as 18, while the 'head 9 has a similar recess as 19.- By virtue of these features the heads 8 and 9 can partially throttle and wholly uncover the respective ports 6 and 7 in alternation. The port which for the time being is the admission port may be throttled to any desired extent, but the area of the exhaust .port for the time being will always be greater than the eflective area of the admission port. 7

In Figs. 2 and 3 the valve 5 is shown at the extreme right, the head 8 wholly uncovering the port 6 and the head 9 partially uncovering the ort 7. It will be assumed that there is ive steam within the valve 5. It

port and the port '6 an outlet port.

therefore follows that the port 7 is an ir i lfit e full area is therefore presented for the exhaust of steam on the left-hand side piston 3, while the port 7 is somewhat restricted. The valve in practice will be constructed with sufficient exhaust lap to hold steam in cylinder until piston has almost completed its stroke, at which point the maximum exhaust port opening will permit piston to commence return stroke without back pressure on the same. When said piston has traveled to the extreme right end of cylinder the valve will open admission port, in which position said valve will cover a portion of both ends ofsaid admission port, still leaving a normal admission port opening. When the piston has practically completed its stroke to the left end of cylinder the valve will fully open exhaust port in right end of cylinder. When said piston has fully completed its stroke to the left the valve will move to the left and open admission port in left end of cylinder, and said valve will cover a portion of each end of this port, although permitting the passage of steam therethrough through a normal admission port. WVhen the piston has traveled to practically the end of its stroke to the right the valve will move to the right and fully open the exhaust ort on the left end of cylinder.

The va ve 5 shown in Fig. 6 is the same in function as the valve 5, the only difference between the two being in external sha e.

I/Vhile I prefer to employ the wear-p ate 2 it is of course not essential that I do so. Several other changes might be made within the scope of my claims; for instance the steam-chest might be made smaller between travel of valve-heads.

What I claim is:

1. The combination of a cylinder, a steam chest having ports for the alternate su ply of steam to and its exhaust from said cy mder,

and a slide valve to control said ports, said valve being adapted to cause alternately during admission 0 steam a reduction of effective area of that port through which the supply of steam is passing relative to the companion port.

2. The combination of a cylinder, a steam chest having ports for the alternate supply of steam to and its exhaust from said cylinder, and a slide valve in said steam chest for partially closing one of said ports and Wholly uncovering the other of said ports in alternation during the supply of steam to and its exhaust from said cylinder.

3. The combination of a cylinder, a steam chest having ports for the alternate su ply of steam to and its exhaust from said cy inder, and a slide valve in said steam chest, having heads adapted to cause alternately during the supply of steam to said cylinder a reduction of effective area of that port through which steam is passing relative to the companion port.

4. The combination of a cylinder, a steam chest having orts for the alternate sup ly of steam to an its exhaust from said cylinder, and a slide valve having heads for controlling the respective ports during the reciprocation of said valve, each head havin an aperture whereby said heads can artia lly cover one and wholly uncover the ot er port in alternation during the admission of steam to and its exhaust from said cylinder.

5. The combination of a steam-chest having ports, and a slide valve in said steamchest, comprising a pair of connected heads each having a recess on the inner side thereof, said heads being adapted to cover partially or wholly uncover in alternation the respective ports, said steam-chest having an inlet for, live steam between said heads and also having outlets for exhaust steam at opposite sides of said heads.

6. The combination of a steam-chest having ports, and a slide valve therein, the steamchest having raised portions on which the valve travels, and the latter comprising two connected heads, the connecting means for the heads having surfaces against which the fluid acts in opposite directions to thereby balance said valve.

7. The combination of a steam-chest having orts, and a slide valve therein for alternate y controlling the ports, said valve comprising two heads, bars connecting the heads, and cross-bars between said other bars, the cross-bars having surfaces to be acted on by a fluid in op osite directions to thereby balance the va ve.

8. The combination of a steam-chest having ports and a slide valve for controlling said ports, said slide valve comprising two connected heads the inner faces of which converge outwardly.

. 9. The combination of a steam-chest having orts and a slide valve therein for alternate y varying the area of said orts during the reciprocatlon thereof, said va ve comprising two connected heads, the inner faces of which converge outward.

In testimony whereof I have hereunto set my hand in presence of two subscribing Witnesses.

MATTHEW J. MALONEY. Witnesses:

P. J. CoNRoY, C. O. OSTERGREN. 

